Question

Найдите производную f(x)=1/(1+cos4x)^5

Answer 1

f'(x)=(1/(1+cos4x)^5)'=(-5)×((1+cos4x)'):

((1+cos4x)^4)=(-5)×(4×(-sin4x))/((1+cos4x)^4)=20×sin4x/((1+cos4x)^4)